Lubricating arrangement for compressors



March 26, 1963 R. v. PRUCHA LUBRICATING ARRANGEMENT FOR COMPRESSORS Filed July 25, 1960 INVENTOR. RICHARD V. PRUCHA HIS ATTORNEY United States Patent Ofi 3,%Z,936 Patented Mar. 26, 19 53 ice 3,082,936 LUBRICATING ARRANGEMENT FQR COMPRESSORS Richard V. Prucha, Louisville, Ky., assignor to General Electric Company, a corporation of New York Filed .luly 25, 1960, Ser. No. 44,955 Claims. (Cl. 230-406) The present invention relates to compressors and is more particularly concerned with an improved means for continuously introducing a small quantity of oil into the cylinder of a hermetic compressor unit.

In one type of hermetic compressor employed in household refrigerator systems, the hermetic casing forms part of the low pressure side of the refrigerating system from which the Compressor withdraws low pressure refrigerant.

The casing also includes a body of oil and means for circulating the oil over the compressor drive motor and other exposed parts of the unit for cooling and lubricating purposes.

The present invention has as its primary object the provision of a low cost means for introducing a metered portion of the circulating oil into the stream of low pressure refrigerant flowing to the compressor cylinder for lubrication of the compressor cylinder and associated parts.

Other objects and advantages of the invention will become apparent as the following description proceeds and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

In carrying out the objects of the present invention there is provided in accordance with the broader aspects of the invention, a compressor structure including a wall portion having a compressor suction or intake port extending therethrough. In order to introduce a small amount of lubricating oil into the compressor cylinder, means are provided for directing a stream of oil onto an area of the wall above and to one side of the inlet end of the intake port. A wire or equivalent means is mounted on the wall in a position such that it slants downwardly from the oil-bathed area into the path of gas entering the intake port inlet end so that oil flowing down wardly along the wire will be picked up by the suction gas flowing to the compressor. Preferably, the means for providing the stream of oil is part of the oil-circulating lubricating and cooling system for the motor driving the hermetic compressor.

For a better understanding of the invention reference may be had to the accompanying drawing in which:

FIG. 1 is an elevational view, partly in section, of a hermetically sealed compressor embodying the present invention; and

FIG. 2 is a sectional view of a portion 'of the compressor unit of FIG. 1 illustrating certain details of the present invention.

With reference to the drawing, there is shown a hermetic compressor unit for use in a refrigerating system ina valve controlled intake port for admitting gas to the compressor cylinder 16 during each down stroke of the piston 8 and a valve controlled exhaust port 13 through which the compressed gas is discharged to an exhaust mufiler 2t) and then outside of the compressor case through a conduit 21 during each upward stroke of the piston 8. During operation of the compressor, low pressure gas entering the case through the suction line 24 passes from the interior of the casing 1 through the motor and housing 4 and into an inlet passage 23 extending through wall 6 and bracket 14 and connecting the interior of the housing 4 with the intake port 15.

For the purpose of cooling the motor, oil is continuously withdrawn from an oil sump 25 provided in the eluding a casing 1 containing a compressor 2 and a motor a 3 hermetically sealed within the casing 1. A supporting frame including a cup-shaped housing 4 having bearings 5 in the vertical wall 6 of the housing, supports a horizontal drive shaft 1!} connecting the motor rotor 7 with the eccentric 13 which drives the piston 8 forming part of the compressor structure 2. It will be understood that the frame is suitably supported, as by means of a plurality of springs (not shown) within the casing 1 in order to protect the motor compressor unit from handling and other severe shocks.

The compressor 2 is supported on the opposite side of the wall 6 from the motor by means 'of a bracket 14 suitably secured to the wall 6. The compressor includes bottom of the case 1 through a conduit 26 by means of an oil pump 27 driven by the shaft 10 and discharged onto the motor from tube 28 having its discharge end 29 positioned in the housing 4 above the motor. The oil then flows from the housing and back into the sump 25 through a tubular element '30 extending through the bottom portion of the housing.

In accordance with the illustrated embodiment of the present invention, lubrication of the compressor cylinder 16 and the valves controlling the inlet and outlet ports 15 and 19 is obtained by diverting a small amount of oil from the oil line 28 onto the wall 6 and metering some of this oil into the suction gas stream entering passage 23.

To this end, there is provided a small aperture 31 in the oil line 28 arranged as shown in FIG. 2 of the drawing to direct a small stream 33 of oil onto an area of the wall 6 to one side of the inlet end of the passage 23 and means, such as a small wire 36, extending from this area in front of the passage and into the path of the gas entering passage 23 for feeding a metered quantity of oil to the compressor.

Preferably the wire or equivalent metering means 36 has the opposite ends thereof spot welded as indicated by the numeral 40 on opposite sides of the inlet to passage 36 so that the Wire is supported in a sloping position such that some of the oil contacting the upper end 41 of the wire or collecting between the wire and the wall 6 will flow downwardly along the wire onto the portion 42 thereof extending in front of the passage 23. Alternatively the wire 36 can be anchored to wall 6 only at one end whereby the free portion can be bent to provide the desired slope and thereby the desired rate at which oil is fed to the compressor.

The use of wire 36 or equivalent element as the metering means for regulating the amount of oil fed to the compressor rather than attempting to size aperture 31 to deliver the required amount of oil and to direct that oil into the passage 23 has a number of advantages. A small aperture in tube 28 designed to deliver the small amount of oil required for lubricating the compressor components directly to the passage 23 could easily become clogged and hence inoperable. For this reason, the aperture 31 is made large enough to avoid this problem and the excess oil is allowed to flow down wall 6 and back to the sump 25. In addition, such an aperture would have a fixed, non-adjustable feed rate. As the size and shape of the wire or equivalent metering means 36 employed in the practice of the present invention, as well as the slope thereof and the space between it and the side wall 6 all effect the amount of oil which will adhere to the wire and be transferred into the path of the gas stream, any one or all of these variables are available for oil feed control purposes. The greater the slope and size or diameter of the wire, the greater the amount of oil which will be retained between it and the wall 6 to flow into the path of the gas entering passage 23. Also, within limits, as the spacing of the wire from the wall 6 is increased, less oil will be trapped'for't-ransfer to the passage 23. A further advantage of the present invention over an arrangement whereby a stream of oil from aperture 31 is introduced directly into passage 23 results from the fact that oil is drawn into passage 23 from wire 36 only when gas is actually flowing to and through the passage to carry that oil to the compressor cylinder. For example, as this gas flow is pulsating for a reciprocating compressor, oil is drawn into the passage only during a down stroke of the compressor piston it or, in other words only when the pulsating flow of gas will transfer the oil to the compressor cylinder.

While a round wire has been illustrated as the preferred transfer or metering means for the practice of the present invention, it will be obvious that the invention is not limited thereto. Any rod, strip, ribbon or filament, or plurality of such elements which do not interfere with the flow of gas into passage 23 and which provide in themselves or in cooperation with the wall 6 means for collecting a small amount of the oil sprayed onto the wall 6 and transferring it into the path of the gas stream in such a manner that the transferred oil will be picked up by the gas stream entering passage 23 can be employed in accordance with the broader aspects of the present invention. Therefore, by the appended claims it is intended to cover all such variations as come within the true spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In combination with a compressor including a-wall portion having a compressor intake passage therein, means for introducing a lubricating oil into the gas stream flowing into said passage comprising means for supplying a continuous stream of oil onto an area of said wall to one side of said passage and sloping wire supported on said wall with the upper end of said wire in the path of the oil flowing downwardly from said area for collecting a portion of said stream of oil and the lower end of said wire extending in front of said passage for transferring some of said portion of said oil to the gas stream entering said passage. 7

2. In combination'with a compressor including a wall portion having "a compressor intake passage extending therethrough with the inlet end thereof in one surface of said wall, means for introducing a lubricating oil into the gas stream flowing into said passage comprising means for supplying a continuous quantity of oil in excess of that required for lubricating said compressor onto an area of said wall surface to one side of said inlet end and a sloping wire supported on said wall surface in the path of the oil flowing downwardly from said area and extending in front of the inlet end of said passage for collecting and transferring a portion of the oil to a point in front of said passage.

3. In combination with a compressor including awall portion having a-compressor intake passage therein, means for introducing a metered quantity of lubricating oil into said compressor comprising means for applying a continuous quantity of oil onto an area of said wall to one side of said passage and a sloping wire supported on said wall in the path of the oil flowing downwardly from said area and extending in front of said intake passage for collecting a portion of said oil and transferring said portion into'the path of the gas stream flowing into said intake passage said wire being secured to said wall portion at only one point whereby its slope can be varied to vary the amount of oil transferred into the path of the gas stream.

4. A hermetically sealed refrigerant compressor comprising a sealed casing having an oil sump therein, a compressor including an intake port for withdrawing low pressure refrigerant from said casing and discharging com pressed refrigerant exteriorly of said casing, an electric motor for driving said compressor, a drive shaft connecting said motor and compressor, a frame supporting said motor and compressor and including a housing supporting the stator component of said motor and surrounding one end of said motor, a passage in one wall of said housing connecting the interior of said housing with the compressor intake port, means including a conduit extending upwardly along said one wall adjacent said passage for directing oil from said sump over said motor, and means for introducing oil into said compressor comprising an opening in said conduit for directing a stream of oil onto an area of said one wall above and to one side of said passage and means for directing the flow of some of said oil into the path of refrigerant flowing through said passage comprising a wire secured to said wall with one end in the area of said wall on which said stream of oil is directed and the other end slanting downwardly from said area across said passage.

5. A hermetically sealed'refrigerant compressor comprising a sealed casing having an oil sump therein, a compressor includingan intake port for withdrawing low pressure refrigerant from said casing and discharging compressed refrigerant ex-teriorly of said casing, an electric motor for driving said compressor, a drive shaft connecting said motor and compressor, a frame supporting said motor and compressor and including a housing supporting the stator component of said motor and surrounding one end of said motor, a passage in one wall of said housing connecting the interior of said housing with the compressor intake port, means including a conduit extending up wardly along said one wall adjacent said passage for directing oil from said sump over said motor, and means for introducing oil into said compressor comprising an opening in said conduit for directing a stream of oil onto an area of said one wall above and to one side of said passage and a sloping wire secured to said wall with the upper end in the path of oil flowing downwardly from said area and the lower end extending in front of said passage for directing the flow of some of said oil stream into the path of refrigerant flowing through said passage.

References Cited in the file of this patent V UNITED STATES PATENTS Re. 17,298 Hele-Shaw et al May 21, 1929 1,564,820 Blanchard Dec. 8, 1925 1,731,774, Gurley Oct. 15, 1929 2,026,238 Loane et al Dec. 31, 1935 2,138,664 Money NOV. 29, 1938 2,643,801 Kollmeyer June 30, 1953 2,738,031 Pyle Mar. 13, 1956 2,852,099 Rernick Sept. 16-, 1958 2,935,244 Dills May 3, 1960 FOREIGN PATENTS 570,780 Great Britain July 23, 1945 

5. A HERMETICALLY SEALED REFRIGERANT COMPRESSOR COMPRISING A SEALED CASING HAVING AN OIL SUMP THEREIN, A COMPRESSOR INCLUDING AN INTAKE PORT FOR WITHDRAWING LOW PRESSURE REFRIGERANT FROM SAID CASING AND DISCHARGING COMPRESSED REFRIGERANT EXTERIORLY OF SAID CASING, AN ELECTRIC MOTOR FOR DRIVING SAID COMPRESSOR, A DRIVE SHAFT CONNECTING SAID MOTOR AND COMPRESSOR, A FRAME SUPPORTING SAID MOTOR AND COMPRESSOR AND INCLUDING A HOUSING SUPPORTING THE STATOR COMPONENT OF SAID MOTOR AND SURROUNDING ONE END OF SAID MOTOR, A PASSAGE IN ONE WALL OF SAID HOUSING CONNECTING THE INTERIOR OF SAID HOUSING WITH THE COMPRESSOR INTAKE PORT, MEANS INCLUDING A CONDUIT EXTENDING UPWARDLY ALONG SAID ONE WALL ADJACENT SAID PASSAGE FOR DIRECTING OIL FROM SAID SUMP OVER SAID MOTOR, AND MEANS FOR INTRODUCING OIL INTO SAID COMPRESSOR COMPRISING AN OPENING IN SAID CONDUIT FOR DIRECTING A STREAM OF OIL ONTO AN AREA OF SAID ONE WALL ABOVE AND TO ONE SIDE OF SAID PASSAGE AND A SLOPING WIRE SECURED TO SAID WALL WITH THE UPPER END IN THE PATH OF OIL FLOWING DOWNWARDLY FROM SAID AREA AND THE LOWER END EXTENDING IN FRONT OF SAID PASSAGE FOR DIRECTING THE FLOW OF SOME OF SAID OIL STREAM INTO THE PATH OF REFRIGERANT FLOWING THROUGH SAID PASSAGE. 